feat: footnotes (#2384)

* feat: footnotes

* feat: proper DOCX support

packages/editor-ext/src/lib/footnotes/footnotes.ts

@@ -0,0 +1,46 @@
+//Source MIT - https://github.com/buttondown/tiptap-footnotes
+import OrderedList from "@tiptap/extension-ordered-list";
+import FootnoteRules from "./rules";
+
+const Footnotes = OrderedList.extend({
+  name: "footnotes",
+  group: "", // removed the default group of the ordered list extension
+  isolating: true,
+  defining: true,
+  draggable: false,
+
+  content() {
+    return "footnote*";
+  },
+  addAttributes() {
+    return {
+      class: {
+        default: "footnotes",
+      },
+    };
+  },
+  parseHTML() {
+    return [
+      {
+        tag: "ol.footnotes",
+        priority: 1000,
+      },
+    ];
+  },
+
+  addKeyboardShortcuts() {
+    return {};
+  },
+  addCommands() {
+    return {};
+  },
+  addInputRules() {
+    return [];
+  },
+
+  addExtensions() {
+    return [FootnoteRules];
+  },
+});
+
+export default Footnotes;